<template>
  <div>
    <div
      class="item"
      v-for="(item, i) in drag.list"
      :key="item.id"
      draggable="true"
      @dragstart="dragstart($event, i)"
      @dragenter="dragenter($event, i)"
      @dragend="dragend"
      @dragover="dragover"
    >
      {{ item.name }}
    </div>
  </div>
</template>
<script setup>
import { reactive } from "vue";
const drag = reactive({
  list: [
    { name: "a", id: 1 },
    { name: "b", id: 2 },
    { name: "c", id: 3 },
    { name: "d", id: 4 },
    { name: "e", id: 5 },
  ],
});

let dragIndex = 0;

function dragstart(e, index) {
  e.stopPropagation();
  dragIndex = index;
  setTimeout(() => {
    e.target.classList.add("moveing");
  }, 0);
}
function dragenter(e, index) {
  e.preventDefault();
  // 拖拽到原位置时不触发
  if (dragIndex !== index) {
    const source = drag.list[dragIndex];
    drag.list.splice(dragIndex, 1);
    drag.list.splice(index, 0, source);

    // 更新节点位置
    dragIndex = index;
  }
}
function dragover(e) {
  e.preventDefault();
  e.dataTransfer.dropEffect = "move";
}
function dragend(e) {
  e.target.classList.remove("moveing");
}
</script>

<style lang="scss" scoped>
.item {
  width: 200px;
  height: 40px;
  line-height: 40px;
  // background-color: #f5f6f8;
  background-color: skyblue;
  text-align: center;
  margin: 10px;
  color: #fff;
  font-size: 18px;
}

.container {
  position: relative;
  padding: 0;
}

.moveing {
  opacity: 0;
}
</style>
